/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package validators;

import java.io.IOException;
import java.io.InputStream;

import javax.servlet.jsp.tagext.PageData;
import javax.servlet.jsp.tagext.TagLibraryValidator;
import javax.servlet.jsp.tagext.ValidationMessage;

/**
 * Example tag library validator that simply dumps the XML version of each page
 * to standard output (which will typically be sent to the file
 * <code>$CATALINA_HOME/logs/catalina.out</code>). To utilize it, simply
 * include a <code>taglib</code> directive for this tag library at the top of
 * your JSP page.
 * 
 * @author Craig McClanahan
 * @version $Revision: 467217 $ $Date: 2006-10-24 11:14:34 +0800 (星期二, 24 十月
 *          2006) $
 */

public class DebugValidator extends TagLibraryValidator {

	// ----------------------------------------------------- Instance Variables

	// --------------------------------------------------------- Public Methods

	/**
	 * Validate a JSP page. This will get invoked once per directive in the JSP
	 * page. This method will return <code>null</code> if the page is valid;
	 * otherwise the method should return an array of
	 * <code>ValidationMessage</code> objects. An array of length zero is also
	 * interpreted as no errors.
	 * 
	 * @param prefix
	 *            The value of the prefix argument in this directive
	 * @param uri
	 *            The value of the URI argument in this directive
	 * @param page
	 *            The page data for this page
	 */
	public ValidationMessage[] validate(String prefix, String uri, PageData page) {

		System.out.println("---------- Prefix=" + prefix + " URI=" + uri
				+ "----------");

		InputStream is = page.getInputStream();
		while (true) {
			try {
				int ch = is.read();
				if (ch < 0)
					break;
				System.out.print((char) ch);
			} catch (IOException e) {
				break;
			}
		}
		System.out.println();
		System.out.println("-----------------------------------------------");
		return (null);

	}

}
